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The Eye. By K arn Rutherford. The eye. In this power point you will learn several facts about eyes and learn the answers to the questions. I hope you will enjoy the power point .
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The Eye By Karn Rutherford
The eye In this power point you will learn several facts about eyes and learn the answers to the questions. I hope you will enjoy the power point .
The human eye works in a manner similar to a camera. They both focus light rays to produce a clear vision. The cornea, is the lens that focuses the light. The cornea is a sort of lens cover, and its main job is to protect the front part of the eye. Apart from the cornea, the eye features another lens, called crystalline, responsible for focusing the light in order to produce a clear image in the retina, the inner layer of the eyeball located along the back hedge of the eye. How does the eye work?
What is colour blindness? Colour-blindness is the inability to distinguish the differences between certain colours. This condition results from an absence of colour-sensitive colour in the cone cells of the retina, the nerve layer at the back of the eye. Game link colour Blind tests – can you read the number?
Why can cats see at night? In your eyes or your cat's, the pupil reacts to changing light by changing size. The pupil gets bigger to let more light in. The lens focuses the light as it passes through. The light strikes a screen called the retina. The retina's nerve cells, called rods and cones, send signals to the brain through the optic nerve, and the brain registers an image.
Why do people have different coloured eyes? The iris give the eye its colour. The pigment is called Melanin. If there are large amount of Melanin present, the colour of the eye would be black, brown or hazel & small amounts would result in light green or light blue eyes. Because of the genes given to the person by their parents during reproduction
Why do older people have to wear glasses? Some people cannot see clearly so they need the help of glasses so they can see. Some people are long sighted which means they cannot see things up close when reading but they can see things far away. Some people are short sighted which means they cannot see things faraway but can see things close up. However people can be short sighted and long sighted.
What are some eye diseases? Cataract Cataract is the clouding of the eye's lens - the part of the eye responsible for focusing light and producing clear, sharp images. Trachoma Trachoma is an infection of the conjunctiva, the thin membrane that covers the outer surface of the eye and the inside lining of the eyelids. It is one of the oldest infectious diseases, dating back several thousand years. It is often not taken seriously and may even be accepted as a fact of life in some countries. Glaucoma Glaucoma is a complicated disease in which damage to the optic nerve leads to progressive, irreversible vision loss.
Interesting facts about eyes.Did you know that: • Your eyes have more than 2 million working parts. • The average blinks per minute is 12 – the average blinks per day is about 10,000. • Only 1/6th of the eyeball is exposed to the outside. • Your eyes will never wear out. • The older we are the less tears we produce
Eye safety • When you are welding you should wear a welding mask cause it can damage. • Things like using glasses would be useful for shading your eyes when it is sunny. • Don’t rub your eyes when your hands are dirty cause you could infect your eyes. • When you are drilling or mowing the lawns you should wear safety goggles.
Bibliography http://www.google.co.nz/search?tbm=isch&hl=en&source=hp&biw=1020&bih=567&q=eyes&gbv=2&aq=f&aqi=g10&aql=&oq=&safe=strict converyoptometrists.com/facts.aspx www.midlandeye.com/eye/facts.php